1. Field of the Invention
This invention relates to casing scrapers used to clean the inside of a well casing.
2. Description of the Prior Art
Casing scrapers are used to remove scale, mud cake, cement sheath and other foreign material from the inside of the casing walls used in oil wells, water wells and the like. The object of the scraping is to smooth the surface of the casing and prepare it for other downhole operations such as packer setting, squeeze tools, etc.
One problem with prior scrapers is that the blades are generally spring loaded onto the scraper body or mandrel, and if the mechanism used to fasten the blades to the body should come loose the entire tool can come apart. This requires a shutdown of the scraping process and the retrieval and repair of the scraper apparatus, resulting in delays and associated expenses.